Optical disk recording/reproducing apparatus

ABSTRACT

An optical disc recording/reproducing apparatus is provided which can obtain the best recording quality. Data is recorded while tracking is displaced by gradually supplying an offset voltage (deviation value) to a tracking error signal, and then reproduction is performed on a recording area. The jitter value (reading state of address information) of biphase data generated from a reproduction RF signal is detected by a biphase jitter detector ( 20 ). Further, on the basis of the offset voltage value (tracking deviation) supplied to the tracking error signal and the detected jitter value of the biphase data, a CPU ( 14 ) determines an offset voltage value where the biphase data has the minimum jitter value, as a tracking deviation for obtaining the best reading state of data, and records the offset voltage value in memory ( 15 ).

TECHNICAL FIELD

The present invention relates to an optical disc recording/reproducingapparatus for recording and reproducing data on a recordable opticaldisc such as a CD-R/RW and a DVD.

BACKGROUND ART

A detrack tolerance value indicating a tolerance of a tracking deviationis one of factors indicating the reproduction capability of an opticaldisc reproducing apparatus for reproducing an optical disc where data isrecorded.

A conventional detrack tolerance detector for detecting a detracktolerance value detects a reproduction state of a disc while graduallyadding a deviation value to a tracking error signal to displace trackingduring the reproduction of the disc, so that a detrack tolerance valueis detected which indicates the reproduction capability of the opticaldisc reproducing apparatus. To be specific, an offset voltage isgradually added to the tracking error signal as a deviation value duringthe reproduction of the disc, and an error value of address datagenerated from a reproduction RF signal is detected as a reproductionstate of the disc while the center voltage of the tracking error signalis shifted. A detrack tolerance value indicating the reproductioncapability of the optical disc reproducing apparatus is detectedaccording to a voltage shifted from the original center voltage when theaddress error value exceeds a predetermined value. In this way, theconventional detrack tolerance detector detects a detrack tolerancevalue (e.g., see Japanese Patent Laid-Open No. 08-249685). Theconventional detrack tolerance detector will be described in detailbelow.

FIG. 2 is a block diagram schematically showing the configuration of aMiniDisc (registered trademark) player using the conventional detracktolerance detector. In FIG. 2, an optical head 31 comprises an opticalsystem which includes a laser diode for emitting laser light, apolarization beam splitter, and an object lens, a light detector fordetecting light reflected from an optical disc 30, and a biaxial devicefor moving the object lens in the radius direction (tracking direction)of the disc and in the contacting/separating direction (focus direction)with respect to the disc.

An RF amplifier 32 generates a reproduction RF signal, a tracking errorsignal, a focus error signal, and so on by arithmetic process from theoutput of the light detector included in the optical head 31, and the RFamplifier 32 outputs the signals to a digital servo circuit 33. Thedigital servo circuit 33 generates an FCS (Focusing Servo)—PWM signaland a TRK (Tracking Servo)—PWM signal from the focus error signal andthe tracking error signal, supplies the signals to an FCK coil and a TRKcoil of the biaxial device via a servo driver 34, and performs focuscontrol and tracking control.

FIG. 3 is a block diagram showing the detail of circuits of the RFamplifier and so on shown in FIG. 2.

In FIG. 3, reference numerals 31A to 31F denote photodetectors servingas light detectors. Among the photodetectors, the photodetectors 31E and31F are photodetectors for generating tracking error signals.

Further, a part surrounded by a dotted line indicates the RF amplifier32, which is constituted of operational amplifiers 36A to 36F forconverting currents outputted by the photodetectors 31A to 31F intovoltages, and operational amplifiers 37A to 37C for performingarithmetic computations on the outputs of the operational amplifiers 36Ato 36F. The operational amplifiers 36E and 36F and the operationalamplifier 37C of these amplifiers are provided for generating trackingerror signals. The operational amplifiers 36E and 36F convert currentsSE and SF outputted from the photodetectors 31E and 31F into voltages.The operational amplifier 37C determines a difference between thevoltages SE and SF (SE−SF) and outputs the difference as the focus errorsignal to the digital servo circuit 33.

A gain adjustment circuit 39 for shifting the center voltage of thetracking error signal is provided on one of the operational amplifiers36E and 36F for converting the currents SE and SF, which are outputtedfrom the photodetectors 31E and 31F, into voltages. The gain adjustmentcircuit 39 changes the gain of the operational amplifier according to adetrack signal (PWM signal) which is supplied from a system controller35 via a lowpass filter 38. Thus, one of the operational amplifiers 36Eand 36F can be changed in gain from the other, thereby shifting thecenter voltage of the tracking error signal by a gain difference.

The following will describe the detection processing of detracktolerance in the MiniDisc player configured as shown in FIGS. 2 and 3.

First, the center voltage of the tracking error signal is set at avoltage value Vc so as to position a light spot at the track center.Then, an offset voltage (deviation value) is added to the tracking errorsignal by controlling the gain adjustment circuit 39 and the centervoltage is increased by one step Va. As shown in FIGS. 4(A) to 4(C), thetracking error signal is biased every time the center voltage increasesby one step Va. By shifting the center voltage thus, the trackingposition is displaced from the track center and an error value ofaddress data generated from the reproduction RF signal is detected. As aresult of displacing tracking, when an address error value exceeds apredetermined value, a shifted voltage value Vmax from the originalcenter voltage value Vc is captured.

Similarly, the center voltage is reduced by one step Va by controllingthe gain adjustment circuit 39. As shown in FIGS. 5(A) to 5(C), thetracking error signal is biased every time the center voltage is reducedby one step Va. By shifting the center voltage thus, the trackingposition is displaced from the track center and an error value ofaddress data generated from the reproduction RF signal is detected. As aresult of displacing tracking, when an address error value exceeds thepredetermined value, a shifted voltage value Vmin from the originalcenter voltage value Vc is captured.

With this processing, the shift voltage values Vmax and Vmin aredetermined which are shifted from the original center voltage value Vcserving as the reproduction limit. A detrack tolerance value indicatingthe reproduction capability of the optical disc reproducing apparatus isderived from the shifted voltage values Vmax and Vmin.

FIG. 6 shows an example of the relationship between a detrack value [am]indicating a deviation distance from the track center and an addresserror value indicating a reproduction state of the disc. As shown inFIG. 6, when the detrack value exceeds, e.g., ±0.2 μm, the address errorvalue starts rapidly increasing. In the case of such a relationship, thedetrack tolerance value (detrack value serving as the reproductionlimit) is, e.g., ±0.2 μm. The detrack value can be determined by avoltage value shifted from the original center voltage value Vc.

On the other hand, when this technique is used to increase thereproduction capability of the optical disc reproducing apparatus, thedetrack tolerance value [μm] is determined in the above-described mannerand a voltage value Vcenter is determined which is shifted from theoriginal center voltage value Vc and corresponds to an intermediatedetrack value [μm]. Then, the determined shifted voltage value Vcenteris added to the tracking error signal to perform reproduction. Thus, itis possible to perform reproduction while obtaining a read marginrelative to the detrack tolerance value serving as the reproductionlimit.

However, when reproduction is performed while the shifted voltage valueVcenter determined thus is added to the tracking error signal, thefollowing problem arises:

The dotted line of FIG. 7 indicates the relationship among a detrackvalue, a jitter value (reading state of data) of data obtained bybinarizing a reproduction RF signal (e.g., an EFM signal and an 8-16modulation signal), a jitter value (reading state of addressinformation) of address data obtained by binarizing an ATIP (AbsoluteTime In Pre-groove) signal having been recorded as address informationon an optical disc, and so on. As indicated by the dotted line, therelationship between the detrack value and the jitter value does notalways change symmetrically with respect to an axis due to variations inthe manufacturing of the optical disc reproducing apparatus and thebiased characteristics of circuits constituting the apparatus. Anasymmetrical change is shown rather than a symmetrical change. Forexample, in the optical disc reproducing apparatus where therelationship between the detrack value and the jitter value ischaracterized as the dotted line shown in FIG. 7, when the detrack valueis ±0.1 μm, the jitter value is minimized, that is, the reproductioncapability is optimized.

Meanwhile, the reproduction RF signal is error corrected afterbinarization. Therefore, even when the reproduction RF signal hassomewhat poor quality, that is, even when data has a somewhat largejitter value, the reproduction capability is improved by errorcorrection.

For this reason, even in the case of the optical disc reproducingapparatus where the relationship between the detrack value and thejitter is characterized as the dotted line of FIG. 7, the relationshipbetween the detrack value and the address error value after errorcorrection is characterized as the solid line of FIG. 7. In this case,the address error value does not change when the detrack value is within±0.2 μm. Thus, in order to perform reproduction while obtaining a readmargin relative to the detrack tolerance value serving as thereproduction limit, reproduction is performed while the shifted voltagevalue Vcenter, which corresponds to the intermediate detrack value (0μm) of the detrack tolerance value (±0.2 μm), is added to the trackingerror signal.

However, even when tracking is controlled while the shifted voltagevalue Vcenter determined thus is added to the tracking error signal, inthe case of reproduction capability degraded by, e.g., the influence oftemperature characteristics or the like of circuits or devices, thefollowing problem arises:

In contrast to the dotted line of FIG. 7, a chain line shows therelationship between the detrack value and the jitter value when thereproduction capability is degraded thus by the influence of thetemperature characteristics or the like of circuits or devices. When thereproduction capability is degraded, the jitter value of data (readingstate of data and address information) exceeds the reproduction limit at0 μm as indicated by the chain line of FIG. 7. That is, whenreproduction is performed using the detrack value derived in theconventional manner, a read margin decreases due to the influence of achange in the environment or the like, resulting in a read error.

Further, the quality of the reproduction RF signal, that is, the jittervalue of data is affected by recording quality as well as the degradedreproduction capability. This suggests the following description:

The dotted line of FIG. 8 shows how a jitter value changes when arecorded disc is reproduced while a light spot of laser light isgradually displaced in the track direction (radius direction). Further,the solid line of FIG. 8 shows how a jitter value changes when a lightspot is caused to track, e.g., the track center to perform reproductionon a recording area. The reproduction is performed after data isrecorded on an unrecorded disc while the light spot is graduallydisplaced in the track direction. As is evident from FIG. 8, a detrackvalue for obtaining the best recording quality and a detrack value forobtaining the best reproduction state are not equal to each other. Whenrecording is performed using a detrack value (±0.1 μm) for obtaining thebest reproduction capability, the recording quality is degraded ascompared with recording using a detrack value of −0.2 μm. Consequently,in order to improve the recording quality, it is necessary to add theshifted voltage value Vcenter, which corresponds to the detrack value(−0.2 μm), to the tracking error signal.

As described above, the detrack value for obtaining the best recordingquality and the detrack value for obtaining the best reproduction stateare not equal to each other. When recording is performed using thedetrack value for obtaining the best reproduction state, the bestrecording quality cannot be obtained. The same problem is found in thecharacteristics of focus and tilt as well as detrack.

In consideration of the problems, in the present invention, data isrecorded while tracking is displaced by gradually adding a deviationvalue to a tracking error signal, and then reproduction is performed ona recording area. A reading state of data, a reading state of addressinformation, or an amplitude value of a reproduction signal is detectedas information indicating recording quality. A tracking deviation forobtaining the best reading state of data, a tracking deviation forobtaining the best reading state of address information, or a trackingdeviation for obtaining the maximum amplitude value of a reproductionsignal is determined. An object is to provide an optical discrecording/reproducing apparatus which can obtain the best recordingquality during data recording by displacing tracking by one of thetracking deviations or an optimum tracking deviation obtained on thebasis of the tracking deviations.

Further, data is recorded while a focus is displaced from a focus pointby gradually adding a deviation value to a focus error signal, and thenreproduction is performed on a recording area. A reading state of data,a reading state of address information, or an amplitude value of areproduction signal is detected as information indicating recordingquality. A deviation from the focus point with the best reading state ofdata, a deviation from the focus point with the best reading state ofaddress information, or a deviation from the focus point with themaximum amplitude value of the reproduction signal is determined. Anobject is to provide an optical disc recording/reproducing apparatuswhich can obtain the best recording quality during data recording bydisplacing the focus from the focus point by one of the deviations or anoptimum deviation from the focus point. The optimum deviation isobtained on the basis of the deviations.

Moreover, data is recorded while an inclination angle (tilt angle) of anoptical axis of light is gradually displaced with respect to a surfaceof an optical disc, and then reproduction is performed on a recordingarea. A reading state of data, a reading state of address information,or an amplitude value of a reproduction signal is detected asinformation indicating recording quality. A tilt angle for obtaining thebest reading state of data, a tilt angle for obtaining the best readingstate of address information, or a tilt angle for obtaining the maximumamplitude value of the reproduction signal is determined. An object isto provide an optical disc recording/reproducing apparatus which canobtain the best recording quality during data recording by inclining theoptical axis by one of the tilt angles or an optimum tilt angle obtainedon the basis of the tilt angles.

DISCLOSURE OF THE INVENTION

An optical disc recording/reproducing apparatus according to claim 1 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a tracking error signal on the basis of theoutput of the optical pickup, the tracking error signal corresponding toa tracking deviation, the optical disc recording/reproducing apparatusperforming tracking according to the tracking error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing tracking by supplying a deviation value to the tracking errorsignal, a unit for recording data while displacing tracking, anddetecting a reading state of address information from the reproductionsignal having been generated by reproduction on a recording area, and aunit for determining and recording a tracking deviation for obtainingthe best reading state of address information, the tracking deviationbeing determined on the basis of the relationship between the detectedreading state of address information and a tracking deviation when datais recorded while tracking is displaced, wherein data is recorded whiletracking is displaced by the recorded tracking deviation.

An optical disc recording/reproducing apparatus according to claim 2 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a tracking error signal on the basis of theoutput of the optical pickup, the tracking error signal corresponding toa tracking deviation, the optical disc recording/reproducing apparatusperforming tracking according to the tracking error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing tracking by supplying a deviation value to the tracking errorsignal, a unit for recording data while displacing tracking, anddetecting a reading state of data from the reproduction signal havingbeen generated by reproduction on a recording area, and a unit fordetermining and recording a tracking deviation for obtaining the bestreading state of data, the tracking deviation being determined on thebasis of the relationship between the detected reading state of data anda tracking deviation when data is recorded while tracking is displaced,wherein data is recorded while tracking is displaced by the recordedtracking deviation.

An optical disc recording/reproducing apparatus according to claim 3 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a tracking error signal on the basis of theoutput of the optical pickup, the tracking error signal corresponding toa tracking deviation, the optical disc recording/reproducing apparatusperforming tracking according to the tracking error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing tracking by supplying a deviation value to the tracking errorsignal, a unit for recording data while displacing tracking, anddetecting an amplitude value of the reproduction signal having beengenerated by reproduction on a recording area, and a unit fordetermining and recording a tracking deviation for obtaining the maximumamplitude value of the reproduction signal, the tracking deviation beingdetermined on the basis of the relationship between the detectedamplitude value of the reproduction signal and a tracking deviation whendata is recorded while tracking is displaced, wherein data is recordedwhile tracking is displaced by the recorded tracking deviation.

An optical disc recording/reproducing apparatus according to claim 4 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a tracking error signal on the basis of theoutput of the optical pickup, the tracking error signal corresponding toa tracking deviation, the optical disc recording/reproducing apparatusperforming tracking according to the tracking error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing tracking by supplying a deviation value to the tracking errorsignal, a unit for recording data while displacing tracking, anddetecting a reading state of address information from the reproductionsignal having been generated by reproduction on a recording area, a unitfor recording data while displacing tracking, and detecting a readingstate of data from the reproduction signal having been generated byreproduction on the recording area, and a unit for determining atracking deviation for obtaining the best reading state of addressinformation and a tracking deviation for obtaining the best readingstate of data, the tracking deviations being determined on the basis ofthe relationship among the detected reading state of addressinformation, the detected reading state of data, and a trackingdeviation when data is recorded while tracking is displaced, the unitdetermining and recording an optimum tracking deviation for recording onthe basis of the deviations, wherein data is recorded while tracking isdisplaced by the recorded tracking deviation.

An optical disc recording/reproducing apparatus according to claim 5 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a tracking error signal on the basis of theoutput of the optical pickup, the tracking error signal corresponding toa tracking deviation, the optical disc recording/reproducing apparatusperforming tracking according to the tracking error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing tracking by supplying a deviation value to the tracking errorsignal, a unit for recording data while displacing tracking, anddetecting a reading state of data from the reproduction signal havingbeen generated by reproduction on a recording area, a unit for recordingdata while displacing tracking, and detecting an amplitude value of thereproduction signal having been generated by reproduction on therecording area, and a unit for determining a tracking deviation forobtaining the best, reading state of data and a tracking deviation forobtaining the maximum amplitude value of the reproduction signal, thetracking deviations being determined on the basis of the relationshipamong the detected reading state of data, the detected amplitude valueof the reproduction signal, and a tracking deviation when data isrecorded while tracking is displaced, the unit determining and recordingan optimum tracking deviation for recording on the basis of thedeviations, wherein data is recorded while tracking is displaced by therecorded tracking deviation.

An optical disc recording/reproducing apparatus according to claim 6 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a tracking error signal on the basis of theoutput of the optical pickup, the tracking error signal corresponding toa tracking deviation, the optical disc recording/reproducing apparatusperforming tracking according to the tracking error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing tracking by supplying a deviation value to the tracking errorsignal, a unit for recording data while displacing tracking, anddetecting a reading state of address information from the reproductionsignal having been generated by reproduction on a recording area, a unitfor recording data while displacing tracking, and detecting an amplitudevalue of the reproduction signal having been generated by reproductionon the recording area, and a unit for determining a tracking deviationfor obtaining the best reading state of address information and atracking deviation for obtaining the maximum amplitude value of thereproduction signal, the tracking deviations being determined on thebasis of the relationship among the detected reading state of addressinformation, the detected amplitude value of the reproduction signal,and a tracking deviation when data is recorded while tracking isdisplaced, the unit determining and recording an optimum trackingdeviation for recording on the basis of the deviations, wherein data isrecorded while tracking is displaced by the recorded tracking deviation.

An optical disc recording/reproducing apparatus according to claim 7 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a tracking error signal on the basis of theoutput of the optical pickup, the tracking error signal corresponding toa tracking deviation, the optical disc recording/reproducing apparatusperforming tracking according to the tracking error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing tracking by supplying a deviation value to the tracking errorsignal, a unit for detecting a reading state of address information fromthe reproduction signal having been generated by light reflected fromthe optical disc when data is recorded with displaced tracking, and aunit for determining and recording a tracking deviation for obtainingthe best reading state of address information, the tracking deviationbeing determined on the basis of the relationship between the detectedreading state of address information and a tracking deviation when datais recorded while tracking is displaced, wherein data is recorded whiletracking is displaced by the recorded tracking deviation.

An optical disc recording/reproducing apparatus according to claim 8 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a focus error signal on the basis of the outputof the optical pickup, the focus error signal corresponding to adeviation of the focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectinga reading state of address information from the reproduction signalhaving been generated by reproduction on a recording area, a unit fordetermining and recording a deviation from the focus point with the bestreading state of address information, the deviation being determined onthe basis of the relationship between the detected reading state ofaddress information and a deviation from the focus point when the datais recorded while the focus of light is displaced from the focus point,wherein data is recorded while the focus of light is displaced from thefocus point by the recorded deviation from the focus point.

An optical disc recording/reproducing apparatus according to claim 9 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a focus error signal on the basis of the outputof the optical pickup, the focus error signal corresponding to adeviation of the focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectinga reading state of data from the reproduction signal having beengenerated by reproduction on a recording area, and a unit fordetermining and recording a deviation from the focus point with the bestreading state of data, the deviation being determined on the basis ofthe relationship between the detected reading state of data and thedeviation from the focus point when data is recorded while the focus oflight is displaced from the focus point, wherein data is recorded whilethe focus of light is displaced from the focus point by the recordeddeviation from the focus point.

An optical disc recording/reproducing apparatus according to claim 10 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a focus error signal on the basis of the outputof the optical pickup, the focus error signal corresponding to adeviation of the focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectingan amplitude value of the reproduction signal having been generated byreproduction on a recording area, and a unit for determining andrecording a deviation from the focus point with the maximum amplitudevalue of the reproduction signal, the deviation being determined on thebasis of the relationship between the detected amplitude value of thereproduction signal and the deviation from the focus point when data isrecorded while the focus of light is displaced from the focus point,wherein data is recorded while the focus of light is displaced from thefocus point by the recorded deviation from the focus point.

An optical disc recording/reproducing apparatus according to claim 11 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a focus error signal on the basis of the outputof the optical pickup, the focus error signal corresponding to adeviation of the focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectinga reading state of address information from the reproduction signalhaving been generated by reproduction on a recording area, a unit forrecording data while displacing the focus of light from the focus point,and detecting a reading state of data from the reproduction signalhaving been generated by reproduction on the recording area, and a unitfor determining a deviation from the focus point with the best readingstate of address information and a deviation from the focus point withthe best reading state of data, the tracking deviations being determinedon the basis of the relationship among the detected reading state ofaddress information, the detected reading state of data, and a deviationfrom the focus point when data is recorded while the focus of light isdisplaced from the focus point, the unit determining and recording anoptimum deviation for recording from the focus point on the basis of thedeviations, wherein data is recorded while the focus of light isdisplaced from the focus point by the recorded deviation from the focuspoint.

An optical disc recording/reproducing apparatus according to claim 12 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a focus error signal on the basis of the outputof the optical pickup, the focus error signal corresponding to adeviation of the focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectinga reading state of data from the reproduction signal having beengenerated by reproduction on a recording area, a unit for recording datawhile displacing the focus of light from the focus point, and detectingan amplitude value of the reproduction signal having been generated byreproduction on the recording area, and a unit for determining adeviation from the focus point with the best reading state of data and adeviation from the focus point with the maximum amplitude value of thereproduction signal, the tracking deviations being determined on thebasis of the relationship among the detected reading state of data, thedetected amplitude value of the reproduction signal, and a deviationfrom the focus point when data is recorded while the focus of light isdisplaced from the focus point, the unit determining and recording anoptimum deviation for recording from the focus point on the basis of thedeviations, wherein data is recorded while the focus of light isdisplaced from the focus point by the recorded deviation from the focuspoint.

An optical disc recording/reproducing apparatus according to claim 13 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a focus error signal on the basis of the outputof the optical pickup, the focus error signal corresponding to adeviation of the focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectinga reading state of address information from the reproduction signalhaving been generated by reproduction on a recording area, a unit forrecording data while displacing the focus of light from the focus point,and detecting an amplitude value of the reproduction signal having beengenerated by reproduction on the recording area, and a unit fordetermining a deviation from the focus point with the best reading stateof address information and a deviation from the focus point with themaximum amplitude value of the reproduction signal, the trackingdeviations being determined on the basis of the relationship among thedetected reading state of data, the detected amplitude value of thereproduction signal, and a deviation from the focus point when data isrecorded while the focus of light is displaced from the focus point, theunit determining and recording an optimum deviation for recording fromthe focus point on the basis of the deviations, wherein data is recordedwhile the focus of light is displaced from the focus point by therecorded deviation from the focus point.

An optical disc recording/reproducing apparatus according to claim 14 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, and a signal generating unit for generating areproduction signal and a focus error signal on the basis of the outputof the optical pickup, the focus error signal corresponding to adeviation of the focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for detecting areading state of address information from the reproduction signal havingbeen generated by light reflected from the optical disc when data isrecorded while the focus of light is displaced from the focus point, anda unit for determining and recording a deviation from the focus pointwith the best reading state of address information, the deviation beingdetermined on the basis of the relationship between the detected readingstate of address information and a deviation from the focus point whendata is recorded while the focus of light is displaced from the focuspoint, wherein data is recorded while the focus of light is displacedfrom the focus point by the recorded deviation from the focus point.

An optical disc recording/reproducing apparatus according to claim 15 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, a signal generating unit for generating a reproductionsignal on the basis of the output of the optical pickup, and a unit forinclining the optical axis of light emitted to the optical disc andadjusting an inclination angle of the optical axis of light with respectto a surface of the optical disc, the optical disc recording/reproducingapparatus adjusting the inclination angle of the optical axis of lightwith respect to the surface of the optical disc to record and reproducedata, wherein the apparatus further comprises a unit for displacing theinclination angle of the optical axis of light with respect to thesurface of the optical disc, a unit for recording data while displacingthe inclination angle of the optical axis of light with respect to thesurface of the optical disc, and detecting a reading state of addressinformation from the reproduction signal having been generated byreproduction on a recording area, and a unit for determining andrecording an inclination angle for obtaining the best reading state ofaddress information, the inclination angle being determined on the basisof the relationship between the detected reading state of addressinformation and the inclination angle when data is recorded while theinclination angle of the optical axis of light is displaced with respectto the surface of the optical disc, wherein data is recorded while theoptical axis of light is inclined by the recorded inclination angle.

An optical disc recording/reproducing apparatus according to claim 16 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, a signal generating unit for generating a reproductionsignal on the basis of the output of the optical pickup, and a unit forinclining the optical axis of light emitted to the optical disc andadjusting an inclination angle of the optical axis of light with respectto a surface of the optical disc, the optical disc recording/reproducingapparatus adjusting the inclination angle of the optical axis of lightwith respect to the surface of the optical disc to record and reproducedata, wherein the apparatus further comprises a unit for displacing theinclination angle of the optical axis of light with respect to thesurface of the optical disc, a unit for recording data while displacingthe inclination angle of the optical axis of light with respect to thesurface of the optical disc, and detecting a reading state of data fromthe reproduction signal having been generated by reproduction on arecording area, and a unit for determining and recording an inclinationangle for obtaining the best reading state of data, the inclinationangle being determined on the basis of the relationship between thedetected reading state of data and an inclination angle when data isrecorded while the inclination angle of the optical axis of light isdisplaced with respect to the surface of the optical disc, wherein datais recorded while the optical axis of light is inclined by the recordedinclination angle.

An optical disc recording/reproducing apparatus according to claim 17 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, a signal generating unit for generating a reproductionsignal on the basis of the output of the optical pickup, and a unit forinclining the optical axis of light emitted to the optical disc andadjusting an inclination angle of the optical axis of light with respectto a surface of the optical disc, the optical disc recording/reproducingapparatus adjusting the inclination angle of the optical axis of lightwith respect to the surface of the optical disc to record and reproducedata, wherein the apparatus further comprises a unit for displacing theinclination angle of the optical axis of light with respect to thesurface of the optical disc, a unit for recording data while displacingthe inclination angle of the optical axis of light with respect to thesurface of the optical disc, and detecting an amplitude value of thereproduction signal having been generated by reproduction on a recordingarea, and a unit for determining and recording an inclination angle forobtaining the maximum amplitude value of the reproduction signal, theinclination angle being determined on the basis of the relationshipbetween the detected amplitude value of the reproduction signal and theinclination angle when data is recorded while the inclination angle ofthe optical axis of light is displaced with respect to the surface ofthe optical disc, wherein data is recorded while the optical axis oflight is inclined by the recorded inclination angle.

An optical disc recording/reproducing apparatus according to claim 18 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, a signal generating unit for generating a reproductionsignal on the basis of the output of the optical pickup, and a unit forinclining the optical axis of light emitted to the optical disc andadjusting an inclination angle of the optical axis of light with respectto a surface of the optical disc, the optical disc recording/reproducingapparatus adjusting the inclination angle of the optical axis of lightwith respect to the surface of the optical disc to record and reproducedata, wherein the apparatus further comprises a unit for displacing theinclination angle of the optical axis of light with respect to thesurface of the optical disc, a unit for recording data while displacingthe inclination angle of the optical axis of light with respect to thesurface of the optical disc, and detecting a reading state of addressinformation from the reproduction signal having been generated byreproduction on a recording area, a unit for recording data whiledisplacing the inclination angle of the optical axis of light withrespect to the surface of the optical disc, and detecting a readingstate of data from the reproduction signal having been generated byreproduction on the recording area, and a unit for determining aninclination angle for obtaining the best reading state of addressinformation and an inclination angle for obtaining the best readingstate of data, the inclination angles being determined on the basis ofthe relationship among the detected reading state of addressinformation, the detected reading state of data, and the inclinationangle when data is recorded while the inclination angle of the opticalaxis of light is displaced with respect to the surface of the opticaldisc, the unit determining and recording an optimum inclination anglefor recording on the basis of the inclination angles, wherein data isrecorded while the optical axis of light is inclined by the recordedinclination angle.

An optical disc recording/reproducing apparatus according to claim 19 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, a signal generating unit for generating a reproductionsignal on the basis of the output of the optical pickup, and a unit forinclining the optical axis of light emitted to the optical disc andadjusting an inclination angle of the optical axis of light with respectto a surface of the optical disc, the optical disc recording/reproducingapparatus adjusting the inclination angle of the optical axis of lightwith respect to the surface of the optical disc to record and reproducedata, wherein the apparatus further comprises a unit for displacing theinclination angle of the optical axis of light with respect to thesurface of the optical disc, a unit for recording data while displacingthe inclination angle of the optical axis of light with respect to thesurface of the optical disc, and detecting a reading state of data fromthe reproduction signal having been generated by reproduction on arecording area, a unit for recording data while displacing theinclination angle of the optical axis of light with respect to thesurface of the optical disc, and detecting an amplitude value of thereproduction signal having been generated by reproduction on therecording area, and a unit for determining an inclination angle forobtaining the best reading state of data and an inclination angle forobtaining the maximum amplitude value of the reproduction signal, theinclination angles being determined on the basis of the relationshipamong the detected reading state of data, the detected amplitude valueof the reproduction signal, and the inclination angle when data isrecorded while the inclination angle of the optical axis of light isdisplaced with respect to the surface of the optical disc, the unitdetermining and recording an optimum inclination angle for recording onthe basis of the inclination angles, wherein data is recorded while theoptical axis of light is inclined by the recorded inclination angle.

An optical disc recording/reproducing apparatus according to claim 20 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, a signal generating unit for generating a reproductionsignal on the basis of the output of the optical pickup, and a unit forinclining the optical axis of light emitted to the optical disc andadjusting an inclination angle of the optical axis of light with respectto a surface of the optical disc, the optical disc recording/reproducingapparatus adjusting the inclination angle of the optical axis of lightwith respect to the surface of the optical disc to record and reproducedata, wherein the apparatus further comprises a unit for displacing theinclination angle of the optical axis of light with respect to thesurface of the optical disc, a unit for recording data while displacingthe inclination angle of the optical axis of light with respect to thesurface of the optical disc, and detecting a reading state of addressinformation from the reproduction signal having been generated byreproduction on a recording area, a unit for recording data whiledisplacing the inclination angle of the optical axis of light withrespect to the surface of the optical disc, and detecting an amplitudevalue of the reproduction signal having been generated by reproductionon the recording area, and a unit for determining an inclination anglefor obtaining the best reading state of address information and aninclination angle for obtaining the maximum amplitude value of thereproduction signal, the inclination angles being determined on thebasis of the relationship among the detected reading state of addressinformation, the detected amplitude value of the reproduction signal,and the inclination angle when data is recorded while the inclinationangle of the optical axis of light is displaced with respect to thesurface of the optical disc, the unit determining and recording anoptimum inclination angle for recording on the basis of the inclinationangles, wherein data is recorded while the optical axis of light isinclined by the recorded inclination angle.

An optical disc recording/reproducing apparatus according to claim 21 ofthe present invention, comprising an optical pickup for emitting lighton a track of an optical disc on which address information is recordedbeforehand, and outputting a signal according to light reflected fromthe optical disc, a signal generating unit for generating a reproductionsignal on the basis of the output of the optical pickup, and a unit forinclining the optical axis of light emitted to the optical disc andadjusting an inclination angle of the optical axis of light with respectto a surface of the optical disc, the optical disc recording/reproducingapparatus adjusting the inclination angle of the optical axis of lightwith respect to the surface of the optical disc to record and reproducedata, wherein the apparatus further comprises a unit for displacing theinclination angle of the optical axis of light with respect to thesurface of the optical disc, a unit for detecting a reading state ofaddress information from the reproduction signal having been generatedby light reflected from the optical disc when data is recorded while theinclination angle of the optical axis of light is displaced with respectto the surface of the optical disc, and a unit for determining andrecording an inclination angle for obtaining the best reading state ofaddress information, the inclination angle being determined on the basisof the relationship between the detected reading state of addressinformation and the inclination angle when data is recorded while theinclination angle of the optical axis of light is displaced with respectto the surface of the optical disc, wherein data is recorded while theoptical axis of light is inclined by the recorded inclination angle.

As described above, according to the present invention, the bestrecording quality can be obtained. Thus, it is possible to obtain asufficient read margin during reproduction, thereby stably performingrecording and reproduction even when recording and reproductioncharacteristics are somewhat degraded by changes in environment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing a structural example of an opticaldisc recording/reproducing apparatus according to an embodiment of thepresent invention;

FIG. 2 is a block diagram schematically showing the configuration of aMiniDisc player using a conventional detrack tolerance detector;

FIG. 3 is a block diagram showing the detail of circuits of an RFamplifier and so on shown in FIG. 2;

FIG. 4 is a waveform chart showing a tracking error signal where adeviation value is added;

FIG. 5 is a waveform chart showing the tracking error signal where adeviation value is added;

FIG. 6 is a diagram showing an example of the relationship between adetrack value and an address error value;

FIG. 7 is a diagram showing an example of the relationship between adetrack value and a jitter value of data obtained by binarizing areproduction RF signal and the relationship between a detrack value andan address error value; and

FIG. 8 is a diagram for explaining conventional problems.

BEST MODE CARRYING OUT THE INVENTION

An embodiment of the present invention will be described below inaccordance with the accompanying drawings. This embodiment is just anexample and the present invention is not limited to the embodimentdescribed below.

FIG. 1 is a block diagram showing a structural example of an opticaldisc recording/reproducing apparatus according to the presentembodiment. In FIG. 1, reference numeral 1 denotes a recordable opticaldisc where address information is recorded beforehand, and referencenumeral 2 denotes an optical pickup which emits laser light as light tobe emitted to the optical disc 1 and outputs a signal according to lightreflected from the optical disc 1. The optical pickup 2 is constitutedof a tracking actuator 3, a focus actuator 4, a tilt actuator 5, a laserdrive circuit 6, a laser diode 7, a light detector 8, and an object lens9.

The laser drive circuit 6 is controlled by an RF amplifier 10 (describedlater) and drives the laser diode 7. The laser diode 7 emits laser lightwith radiation power corresponding to an amount of current supplied bythe laser drive circuit 6. The object lens 9 condenses laser lightemitted from the laser diode 7 and forms a light spot on the opticaldisc 1. The tracking actuator 3 moves the object lens 9 in the radiusdirection (tracking direction) of the disc and adjusts the trackingposition of the light spot. The focus actuator 4 moves the object lens 9in the contacting/separating direction (focus direction) with respect tothe disc and adjusts the focus position of-laser light. The tiltactuator 5 changes the angle of the object lens 9 and adjusts theinclination angle of the optical axis of laser light with respect to asurface of the optical disc 1. The light detector 8 receives lightreflected from the optical disc 1, converts the light into an electricsignal, and outputs the signal.

Reference numeral 10 denotes the RF amplifier which serves as a signalgenerating unit for generating a tracking error signal according to adeviation from the track center (predetermined tracking position) of alight spot, a focus error signal according to a deviation of the focusof laser light from the surface of the optical disc 1 (focus point), anda reproduction RF signal as a reproduction signal, by arithmetic on thebasis of the output signal (electric signal) of the light detector 8.Further, the RF amplifier 10 transmits, to the laser drive circuit 6, asignal generated according to an instruction from a CPU 14 (describedlater) or a signal corresponding to data inputted from a recording dataencoder circuit 22, and controls the on/off of laser output from thelaser diode 7 and the radiation power of laser light.

In the following explanation, the predetermined tracking position isinitially set at the track center. Needless to say, the predeterminedtracking position is not limited to the track center. Although the focuspoint is initially set on the surface of the optical disc 1 in thefollowing explanation, naturally the focus point is not limited to thesurface of the optical disc 1.

Reference numeral 11 denotes a tracking actuator drive for driving thetracking actuator 3, reference numeral 12 denotes a focus actuator drivefor driving the focus actuator 4, and reference numeral 13 denotes atilt actuator drive for driving the tilt actuator 5.

Reference numeral 14 denotes the CPU for controlling the entireapparatus, and reference numeral 15 denotes memory serving as a storagedevice capable of exchanging data with the CPU 14.

Reference numeral 16 denotes a servo controller which controls thetracking actuator drive 11 according to the tracking error signal todrive the tracking actuator 3 such that a light spot tracks the trackcenter. The servo controller controls the focus actuator drive 12according to the focus error signal to drive the focus actuator 4 suchthat laser light is focused on the surface of the optical disc 1.Further, the servo controller controls the tilt actuator drive 13according to a command from the CPU 14 to drive the tilt actuator 5 suchthat the light detector 8 efficiently receives reflected light.

Reference numeral 17 denotes a data slicer which binarizes thereproduction RF signal generated by the RF amplifier 10 and converts thesignal into data (digital signal). Reference numeral 18 denotes a datajitter detector which outputs to the CPU 14 a signal corresponding tothe jitter value of the data.

Reference numeral 19 denotes a biphase data generating circuit whichgenerates biphase data from the reproduction RF signal generated by theRF amplifier 10. On both ends of the track of the optical disc 1, anATIP signal serving as address information forms waves while beingfrequency modulated. The reproduction RF signal includes a componenthaving been frequency modulated. The biphase data generating circuit 19extracts the frequency modulated component, binarizes the component, andperforms frequency demodulation on the component, so that biphase data(address data) is generated from the reproduction RF signal. Referencenumeral 20 denotes a biphase data jitter detector which outputs to theCPU 14 a signal corresponding to the jitter value of the biphase data.

Reference numeral 21 denotes an RF amplitude detector which detects anamplitude value of the reproduction RF signal generated by the RFamplifier 10 and outputs the amplitude value to the CPU 14.

Reference numeral 22 denotes a recording data encoding circuit whichencodes data to be recorded on the optical disc 1 in response to aninstruction from the CPU 14 and outputs the data to the RF amplifier 10.

The following will discuss the operations of a tracking servo system ofthe optical disc recording/reproducing apparatus configured thus.

When current is supplied to the laser diode 7 by the laser drive circuit6, the laser diode 7 emits laser light with radiation powercorresponding to an amount of the current. The laser light is focused atthe track center on the surface of the optical disc 1 by the object lens9 and forms a light spot. Light reflected from the optical disc 1 passesthrough the object lens 9 again and is received by the light detector 8.The light detector 8 converts the received reflected light into anelectric signal and outputs the signal to the RF amplifier 10.

As described above, the RF amplifier 10 generates the tracking errorsignal according to a deviation from the track center of the light spoton the basis of the electric signal from the light detector 8, andoutputs the signal to the servo controller 16. In normal times, theservo controller 16 outputs a tracking control signal (PWM signal),which is generated on the basis of the tracking error signal, to thetracking actuator drive 11. The tracking actuator drive 11 supplies acurrent corresponding to the tracking control signal to the trackingactuator 3, and moves the object lens 9 in the tracking direction tocause the light spot to track the track center.

The RF amplifier 10 or the servo controller 16 has the function ofadding an offset voltage (voltage for increasing or reducing the centervoltage value of the tracking error signal) as a deviation value to thetracking error signal. When the CPU 14 instructs the RF amplifier 10 orthe servo controller 16 to add the offset voltage to the tracking errorsignal, the servo controller 16 generates the tracking control signal onthe basis of the tracking error signal where the offset voltage isadded. The tracking actuator drive 11 supplies a current correspondingto the tracking control signal to the tracking actuator 3, and moves theobject lens 9 in the tracking direction to cause the light spot to tracka tracking position displaced from the track center according to theoffset voltage.

The following will discuss the operations of a focus servo system.

As described above, the RF amplifier 10 generates the focus error signalaccording to a deviation of the focus of laser light from the surface ofthe optical disc 1 on the basis of the electric signal outputted fromthe light detector 8 included in the optical pickup 2, and outputs thesignal to the servo controller 16. In normal times, the servo controller16 outputs a focus control signal (PWM signal), which is generated onthe basis of the focus error signal, to the focus actuator drive 12. Thefocus actuator drive 12 supplies a current corresponding to the focuscontrol signal to the focus actuator 4, and moves the object lens 9 inthe focus direction so as to focus laser light on the surface of theoptical disc 1.

The RF amplifier 10 or the servo controller 16 has the function ofadding an offset voltage (voltage for increasing or reducing the centervoltage of the focus error signal) as a deviation value to the focuserror signal. When the CPU 14 instructs the RF amplifier 10 or the servocontroller 16 to add the offset voltage to the focus error signal, theservo controller 16 generates the focus control signal on the basis ofthe focus error signal where the offset voltage is added. The focusactuator drive 12 supplies a current corresponding to the focus controlsignal to the focus actuator 4, and moves the object lens 9 in the focusdirection so as to focus laser light on a position displaced from thesurface of the optical disc 1 according to the offset voltage.

Tilt control will be discussed below. The servo controller 16 outputs atilt control signal to the tilt actuator drive 13 in response to aninstruction from the CPU 14. The tilt actuator drive 13 supplies acurrent corresponding to the tilt control signal to the tilt actuator 5.The tilt actuator 5 inclines the object lens 9 by an angle correspondingto an amount of the supplied current.

The recording of data will be discussed below. In response to aninstruction from the CPU 14, the recording data encoder circuit 22encodes data to be recorded on the optical disc 1 and outputs the datato the RF amplifier 10. The RF amplifier 10 sends a signal on the basisof the encoded data to the laser drive circuit 6 included in the opticalpickup 2. The laser drive circuit 6 drives the laser diode 7 on thebasis of the signal sent from the RF amplifier 10, so that pits areformed on the track of the optical disc 1 according to “0” and “1” ofthe encoded data.

According to the above description, the following will discussprocessing for determining a tracking deviation for obtaining the bestreading state of address information in the optical discrecording/reproducing apparatus.

First, while recording data on the optical disc 1, the CPU 14 instructsthe RF amplifier 10 or the servo controller 16 to gradually add anoffset voltage, which serves as a deviation value, to the tracking errorsignal. However, as described above, the center voltage value of thetracking error signal is initially set such that a spot (light spot) oflaser light condensed by the object lens 9 tracks the track center inthe present embodiment.

The RF amplifier 10 or the servo controller 16 gradually adds the offsetvoltage to the tracking error signal in response to the instruction fromthe CPU 14. As described above, in the present embodiment,initialization is performed such that a light spot tracks the trackcenter. Thus, by adding the offset voltage to the tracking error signal,the light spot is displaced from the track center and tracking isshifted. Further, an offset voltage value and a tracking deviation arein proportion to each other.

After the offset voltage within a predetermined range is added to thetracking error signal, recording is ended. The offset voltage is addedso as to displace the light spot from the track center to the inside andthe outside of the optical disc 1.

Thereafter, the offset voltage is added to the tracking error signal toreproduce an area where data is recorded. During reproduction, laserlight is emitted with a radiation power for reproduction. For example,the tracking position in the reproduction is the track center which isset initially. Laser light is condensed by the object lens 9 and isemitted to the optical disc 1. Light reflected from the optical disc 1passes through the object lens 9 again and is incident on the lightdetector 8. The light detector 8 converts the received reflected lightinto an electric signal and outputs the signal to the RF amplifier 10.The RF amplifier 10 generates the reproduction RF signal from theelectric signal.

In the present embodiment, in order to detect a jitter value of biphasedata as a reading state of address information, an ATIP signal (addressinformation) included in the generated reproduction RF signal isconverted into biphase data (address data) in the biphase datagenerating circuit 19 and is inputted to the biphase data jitterdetector 20. The biphase data jitter detector 20 detects the jittervalue of the biphase data and outputs the value to the CPU 14.

According to a tracking deviation, that is, the offset voltage valueadded to the tracking error signal and the detected jitter value of thebiphase data, the CPU 14 determines an offset voltage value whichminimizes the jitter value of the biphase data, and records the offsetvoltage value in the memory 15.

In this way, in the present embodiment, an offset voltage value isdetermined which minimizes the jitter value of the biphase data, as atracking deviation for obtaining the best reading state of addressinformation. As described above, in the present embodiment,initialization is performed such that a light spot tracks the trackscenter. Thus, a tracking deviation is equal to a deviation from thetrack center. Moreover, it is possible to distinguish whether thedeviation is made to the inside or the outside.

According to the present embodiment, for example, when products aremanufactured in a factory, the above-described processing is performedto record, in the memory, an offset voltage value corresponding to atracking deviation for obtaining the best reading state of addressinformation. When the product is actually used by the user, the offsetvoltage value recorded in the memory is added to the tracking errorsignal to record data. Thus, it is possible to record data with the bestreading state of address information, thereby improving the recordingquality of the optical disc recording/reproducing apparatus.

The following will discuss processing for determining a trackingdeviation for obtaining the best reading state of data in the opticaldisc recording/reproducing apparatus.

First, as described above, data is recorded while an offset voltageserving as a deviation value is gradually added to the tracking errorsignal, and then reproduction is performed on the area.

In the present embodiment, in order to detect a jitter value of data asa reading state of the data, the reproduction RF signal is binarized andconverted into data in the data slicer 17, and the signal is inputted tothe data jitter detector 18. The data jitter detector 18 detects ajitter value of the data and outputs the jitter value to the CPU 14.

According to a tracking deviation, that is, an offset voltage valueadded to the tracking error signal and a jitter value of the data, theCPU 14 determines an offset voltage value which minimizes the jittervalue of the data, and records the offset voltage value in the memory15.

In this way, in the present embodiment, an offset voltage value wheredata has the minimum jitter value is determined as a tracking deviationfor obtaining the best reading state of recorded data.

According to the present embodiment, for example, when products aremanufactured in a factory, the above-described processing is performedto record, in the memory, an offset voltage value corresponding to atracking deviation for obtaining the best reading state of data. Whenthe product is actually used by the user, the offset voltage valuerecorded in the memory is added to the tracking error signal to recorddata. Thus, it is possible to record data with the best reading state ofthe data, thereby improving the recording quality of the optical discrecording/reproducing apparatus.

The following will discuss processing for determining a trackingdeviation which collectively improves the reading state of previouslyrecorded address information and the reading state of recorded data inthe optical disc recording/reproducing apparatus. The present embodimentdetermines a tracking deviation where the reproduction RF signal has themaximum amplitude value.

First, as described above, data is recorded while an offset voltageserving as a deviation value is gradually added to the tracking errorsignal, and then reproduction is performed on the area.

The reproduction RF signal generated in the RF amplifier 10 is inputtedto the RF amplitude detector 21 and the amplitude value of the signal isdetected. According to a tracking deviation, that is, an offset voltagevalue added to the tracking error signal and an amplitude value of thereproduction RF signal detected by the RF amplitude detector 21, the CPU14 determines an offset voltage value where the reproduction RF signalhas the maximum amplitude value, and records the offset voltage value inthe memory 15.

In this way, in the present embodiment, an offset voltage value wherethe reproduction RF signal has the maximum amplitude value is determinedas a tracking deviation which collectively improves the reading state ofpreviously recorded address information and the reading state ofrecorded data.

According to the present embodiment, for example, when products aremanufactured in a factory, the above-described processing is performedto record, in the memory, an offset voltage value corresponding to atracking deviation for obtaining the maximum amplitude value of thereproduction RF signal. When the product is actually used by the user,the offset voltage value recorded in the memory is added to the trackingerror signal to record data. Thus, it is possible to record data so asto collectively improve the reading state of previously recorded addressinformation and the reading state of recorded data, thereby improvingthe recording quality of the optical disc recording/reproducingapparatus.

The above explanation described the determination of the offset voltagevalue where biphase data has the minimum jitter value, the offsetvoltage value where data has the minimum jitter value, and the offsetvoltage value where the reproduction RF signal has the maximumamplitude. As a matter of course, these offset voltage values may becombined to determined an optimum offset voltage value for recording.

For example, the following processing is also applicable: by using thereproduction RF signal generated by reproducing an area where data hasbeen recorded while tracking is displaced, an offset voltage value wherebiphase data has the minimum jitter value and an offset voltage valuewhere data has the minimum jitter value are determined, and an optimumoffset voltage value for recording is determined according to theequation below and is recorded in the memory 15. The optimum offsetvoltage value collectively improves the reading state of previouslyrecorded address information and the reading state of recorded data.z=a(x+y)where x=an offset voltage value where biphase data has the minimumjitter value, y=an offset voltage value where data has the minimumjitter value, z=an optimum offset voltage value for recording, and avalue a is set such that z has a value between x and y.

As an offset voltage value corresponding to an optimum trackingdeviation for recording that collectively improves the reading state ofpreviously recorded address information and the reading state ofrecorded data, an offset voltage value may be determined as follows: adifference between the offset voltage value where biphase data has theminimum jitter value and the offset voltage value where data has theminimum jitter value is multiplied by a certain ratio.

The same effect can be obtained also by combining the offset voltagevalue where data has the minimum jitter value and the offset voltagevalue where the reproduction RF signal has the maximum amplitude value,and combining the offset voltage value where biphase data has theminimum jitter value and the offset voltage value where the reproductionRF signal has the maximum amplitude value.

The above explanation described processing for recording data whilegradually adding a deviation value to the tracking error signal, andthen reproducing the area to determine an optimum offset voltage valuefor recording. Since the jitter value of biphase data can be detectedeven during data recording, the jitter value of biphase data may bedetermined during recording.

When data is recorded on the optical disc 1, as described above, pitsare formed on the track of the optical disc 1 according to “0” and “1”of the encoded data. That is, during recording, the radiation power oflaser light is controlled so as to emit laser light with high radiationpower when pits are formed. Laser light is emitted with low radiationpower when no pit is formed. The low radiation power is at the samelevel as the reproduction of data. Thus, the jitter value of biphasedata can be detected on the basis of the reproduction RF signal which isobtained when laser light is emitted with the radiation power forreproduction.

In this way, by determining the jitter value of biphase data duringrecording, it is possible to eliminate the need for reproduction afterrecording, thereby shortening processing time.

The above explanation described processing for improving the recordingquality of the optical disc recording/reproducing apparatus bydisplacing tracking. Similarly, the recording quality of the opticaldisc recording/reproducing apparatus may be improved by displacing thefocus of laser light from the surface of the optical disc 1 (focuspoint).

That is, the following processing is also applicable: a deviation value(offset voltage) is gradually added to the focus error signal, data isrecorded while the focus of laser light is displaced from the surface ofthe optical disc 1 (focus point), the area is reproduced to detect thejitter value of biphase data, the jitter value of data, and theamplitude value of the reproduction RF signal, and an offset voltagevalue where biphase data has the minimum jitter value, an offset voltagevalue where data has the minimum jitter value, and an offset voltagevalue where the reproduction RF signal has the maximum amplitude valueare determined and recorded. Thus, the recorded offset voltage value isadded to the focus error signal and data can be recorded while the focusposition of laser light is displaced from the focus point to an optimumposition for recording, thereby improving the recording quality of theoptical disc recording/reproducing apparatus. As described above, thejitter value of the biphase data can be determined during recording.

Similarly, the recording quality of the optical discrecording/reproducing apparatus can be improved by adjusting aninclination angle (tilt angle) of the optical axis of laser light withrespect to the surface of the optical disc 1. That is, the followingprocessing is also applicable: while data is recorded on the opticaldisc 1, the CPU 14 instructs the servo controller 16 to graduallydisplace the inclination angle of the optical axis of laser light withrespect to the surface of the optical disc 1, the recorded area isreproduced after recording, and a jitter value of biphase data, a jittervalue of data, and an amplitude value of the reproduction RF signal aredetected, and a tilt angle where the biphase data has the minimum jittervalue, a tilt angle where the data has the minimum jitter value, and atilt angle where the reproduction RF signal has the maximum amplitudevalue are determined and are recorded in the memory 15 on the basis ofthe inclination angle provided for the servo controller 16, the detectedjitter value of the biphase data, the jitter value of the data, and theamplitude value of the reproduction RF signal. With this processing,during data recording, the optical axis of laser light is inclined so asto have the recorded inclination angle with respect to the surface ofthe optical disc. Thus, it is possible to efficiently receive reflectedlight on a photoreceptor, thereby improving the recording quality of theoptical disc recording/reproducing apparatus. As described above, thejitter value of biphase data can be determined during recording.

1. An optical disc recording/reproducing apparatus, comprising anoptical pickup for emitting light on a track of an optical disc on whichaddress information is recorded beforehand, and outputting a signalaccording to light reflected from the optical disc, and a signalgenerating unit for generating a reproduction signal and a trackingerror signal on a basis of an output of the optical pickup, the trackingerror signal corresponding to a tracking deviation, the optical discrecording/reproducing apparatus performing tracking according to thetracking error signal to record and reproduce data, wherein saidapparatus further comprises: a unit for displacing tracking by supplyinga deviation value to the tracking error signal, a unit for recordingdata while displacing tracking, and detecting a reading state of addressinformation from the reproduction signal having been generated byreproduction on a recording area, and a unit for determining andrecording a tracking deviation for obtaining a best reading state ofaddress information, the tracking deviation being determined on a basisof a relationship between the detected reading state of addressinformation and a tracking deviation when data is recorded whiletracking is displaced, wherein data is recorded while tracking isdisplaced by the recorded tracking deviation.
 2. An optical discrecording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, and a signal generating unit forgenerating a reproduction signal and a tracking error signal on a basisof an output of the optical pickup, the tracking error signalcorresponding to a tracking deviation, the optical discrecording/reproducing apparatus performing tracking according to thetracking error signal to record and reproduce data, wherein theapparatus further comprises: a unit for displacing tracking by supplyinga deviation value to the tracking error signal, a unit for recordingdata while displacing tracking, and detecting a reading state of datafrom the reproduction signal having been generated by reproduction on arecording area, and a unit for determining and recording a trackingdeviation for obtaining a best reading state of data, the trackingdeviation being determined on a basis of a relationship between thedetected reading state of data and a tracking deviation when data isrecorded while tracking is displaced, wherein data is recorded whiletracking is displaced by the recorded tracking deviation.
 3. An opticaldisc recording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, and a signal generating unit forgenerating a reproduction signal and a tracking error signal on a basisof an output of the optical pickup, the tracking error signalcorresponding to a tracking deviation, the optical discrecording/reproducing apparatus performing tracking according to thetracking error signal to record and reproduce data, wherein theapparatus further comprises: a unit for displacing tracking by supplyinga deviation value to the tracking error signal, a unit for recordingdata while displacing tracking, and detecting an amplitude value of thereproduction signal having been generated by reproduction on a recordingarea, and a unit for determining and recording a tracking deviation forobtaining a maximum amplitude value of the reproduction signal, thetracking deviation being determined on a basis of a relationship betweenthe detected amplitude value of the reproduction signal and a trackingdeviation when data is recorded while tracking is displaced, whereindata is recorded while tracking is displaced by the recorded trackingdeviation.
 4. An optical disc recording/reproducing apparatus,comprising an optical pickup for emitting light on a track of an opticaldisc on which address information is recorded beforehand, and outputtinga signal according to light reflected from the optical disc, and asignal generating unit for generating a reproduction signal and atracking error signal on a basis of an output of the optical pickup, thetracking error signal corresponding to a tracking deviation, the opticaldisc recording/reproducing apparatus performing tracking according tothe tracking error signal to record and reproduce data, wherein theapparatus further comprises: a unit for displacing tracking by supplyinga deviation value to the tracking error signal, a unit for recordingdata while displacing tracking, and detecting a reading state of addressinformation from the reproduction signal having been generated byreproduction on a recording area, a unit for recording data whiledisplacing tracking, and detecting a reading state of data from thereproduction signal having been generated by reproduction on therecording area, and a unit for determining a tracking deviation forobtaining a best reading state of address information and a trackingdeviation for obtaining a best reading state of data, the trackingdeviations being determined on a basis of a relationship among thedetected reading state of address information, the detected readingstate of data, and a tracking deviation when data is recorded whiletracking is displaced, the unit determining and recording an optimumtracking deviation for recording on a basis of the deviations, whereindata is recorded while tracking is displaced by the recorded trackingdeviation.
 5. An optical disc recording/reproducing apparatus,comprising an optical pickup for emitting light on a track of an opticaldisc on which address information is recorded beforehand, and outputtinga signal according to light reflected from the optical disc, and asignal generating unit for generating a reproduction signal and atracking error signal on a basis of an output of the optical pickup, thetracking error signal corresponding to a tracking deviation, the opticaldisc recording/reproducing apparatus performing tracking according tothe tracking error signal to record and reproduce data, wherein theapparatus further comprises: a unit for displacing tracking by supplyinga deviation value to the tracking error signal, a unit for recordingdata while displacing tracking, and detecting a reading state of datafrom the reproduction signal having been generated by reproduction on arecording area, a unit for recording data while displacing tracking, anddetecting an amplitude value of the reproduction signal having beengenerated by reproduction on the recording area, and a unit whichdetermines a tracking deviation for obtaining a best reading state ofdata and a tracking deviation for obtaining a maximum amplitude value ofthe reproduction signal, the tracking deviations being determined on abasis of a relationship among the detected reading state of data, thedetected amplitude value of the reproduction signal, and a trackingdeviation when data is recorded while tracking is displaced, the unitdetermining and recording an optimum tracking deviation for recording ona basis of the deviations, wherein data is recorded while tracking isdisplaced by the recorded tracking deviation.
 6. An optical discrecording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, and a signal generating unit forgenerating a reproduction signal and a tracking error signal on a basisof an output of the optical pickup, the tracking error signalcorresponding to a tracking deviation, the optical discrecording/reproducing apparatus performing tracking according to thetracking error signal to record and reproduce data, wherein theapparatus further comprises: a unit for displacing tracking by supplyinga deviation value to the tracking error signal, a unit for recordingdata while displacing tracking, and detecting a reading state of addressinformation from the reproduction signal having been generated byreproduction on a recording area, a unit for recording data whiledisplacing tracking, and detecting an amplitude value of thereproduction signal having been generated by reproduction on therecording area, and a unit for determining a tracking deviation forobtaining a best reading state of address information and a trackingdeviation for obtaining a maximum amplitude value of the reproductionsignal, the tracking deviations being determined on a basis of arelationship among the detected reading state of address information,the detected amplitude value of the reproduction signal, and a trackingdeviation when data is recorded while tracking is displaced, the unitdetermining and recording an optimum tracking deviation for recording ona basis of the deviations, wherein data is recorded while tracking isdisplaced by the recorded tracking deviation.
 7. An optical discrecording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, and a signal generating unit forgenerating a reproduction signal and a tracking error signal on a basisof an output of the optical pickup, the tracking error signalcorresponding to a tracking deviation, the optical discrecording/reproducing apparatus performing tracking according to thetracking error signal to record and reproduce data, wherein theapparatus further comprises: a unit for displacing tracking by supplyinga deviation value to the tracking error signal, a unit for detecting areading state of address information from the reproduction signal havingbeen generated by light reflected from the optical disc when data isrecorded with displaced tracking, and a unit for determining andrecording a tracking deviation for obtaining a best reading state ofaddress information, the tracking deviation being determined on a basisof a relationship between the detected reading state of addressinformation and the tracking deviation when data is recorded whiletracking is displaced, wherein data is recorded while tracking isdisplaced by the recorded tracking deviation.
 8. An optical discrecording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, and a signal generating unit forgenerating a reproduction signal and a focus error signal on a basis ofan output of the optical pickup, the focus error signal corresponding toa deviation of a focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises: a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectinga reading state of address information from the reproduction signalhaving been generated by reproduction on a recording area, and a unitfor determining and recording a deviation from the focus point with abest reading state of address information, the deviation beingdetermined on a basis of a relationship between the detected readingstate of address information and a deviation from the focus point whenthe data is recorded while the focus of light is displaced from thefocus point, wherein data is recorded while the focus of light isdisplaced from the focus point by the recorded deviation from the focuspoint.
 9. An optical disc recording/reproducing apparatus, comprising anoptical pickup for emitting light on a track of an optical disc on whichaddress information is recorded beforehand, and outputting a signalaccording to light reflected from the optical disc, and a signalgenerating unit for generating a reproduction signal and a focus errorsignal on a basis of an output of the optical pickup, the focus errorsignal corresponding to a deviation of a focus of emitted light from afocus point, the optical disc recording/reproducing apparatus aligningthe focus of light with the focus point according to the focus errorsignal to record and reproduce data, wherein the apparatus furthercomprises: a unit for displacing the focus of light from the focus pointby supplying a deviation value to the focus error signal, a unit forrecording data while displacing the focus of light from the focus point,and detecting a reading state of data from the reproduction signalhaving been generated by reproduction on a recording area, and a unitfor determining and recording a deviation from the focus point with abest reading state of data, the deviation being determined on a basis ofa relationship between the detected reading state of data and thedeviation from the focus point when data is recorded while the focus oflight is displaced from the focus point, wherein data is recorded whilethe focus of light is displaced from the focus point by the recordeddeviation from the focus point.
 10. An optical discrecording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, and a signal generating unit forgenerating a reproduction signal and a focus error signal on a basis ofan output of the optical pickup, the focus error signal corresponding toa deviation of a focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises: a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectingan amplitude value of the reproduction signal having been generated byreproduction on a recording area, and a unit for determining andrecording a deviation from the focus point with a maximum amplitudevalue of the reproduction signal, the deviation being determined on abasis of a relationship between the detected amplitude value of thereproduction signal and the deviation from the focus point when data isrecorded while the focus of light is displaced from the focus point,wherein data is recorded while the focus of light is displaced from thefocus point by the recorded deviation from the focus point.
 11. Anoptical disc recording/reproducing apparatus, comprising an opticalpickup for emitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, and a signal generating unit forgenerating a reproduction signal and a focus error signal on a basis ofan output of the optical pickup, the focus error signal corresponding toa deviation of a focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises: a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for recording datawhile displacing the focus of light from the focus point, and detectinga reading state of address information from the reproduction signalhaving been generated by reproduction on a recording area, a unit forrecording data while displacing the focus of light from the focus point,and detecting a reading state of data from the reproduction signalhaving been generated by reproduction on the recording area, and a unitfor determining a deviation from the focus point with a best readingstate of address information and a deviation from the focus point with abest reading state of data, the deviations being determined on a basisof a relationship among the detected reading state of addressinformation, the detected reading state of data, and a deviation fromthe focus point when data is recorded while the focus of light isdisplaced from the focus point, the unit determining and recording anoptimum deviation for recording from the focus point on a basis of thedeviations, wherein data is recorded while the focus of light isdisplaced from the focus point by the recorded deviation from the focuspoint.
 12. An optical disc recording/reproducing apparatus, comprisingan optical pickup for emitting light on a track of an optical disc onwhich address information is recorded beforehand, and outputting asignal according to light reflected from the optical disc, and a signalgenerating unit for generating a reproduction signal and a focus errorsignal on a basis of an output of the optical pickup, the focus errorsignal corresponding to a deviation of a focus of emitted light from afocus point, the optical disc recording/reproducing apparatus aligningthe focus of light with the focus point according to the focus errorsignal to record and reproduce data, wherein the apparatus furthercomprises: a unit for displacing the focus of light from the focus pointby supplying a deviation value to the focus error signal, a unit forrecording data while displacing the focus of light from the focus point,and detecting a reading state of data from the reproduction signalhaving been generated by reproduction on a recording area, a unit forrecording data while displacing the focus of light from the focus point,and detecting an amplitude value of the reproduction signal having beengenerated by reproduction on the recording area, and a unit fordetermining a deviation from the focus point with a best reading stateof data and a deviation from the focus point with a maximum amplitudevalue of the reproduction signal, the deviations being determined on abasis of a relationship among the detected reading state of data, thedetected amplitude value of the reproduction signal, and a deviationfrom the focus point when data is recorded while the focus of light isdisplaced from the focus point, the unit determining and recording anoptimum deviation for recording from the focus point on a basis of thedeviations, wherein data is recorded while the focus of light isdisplaced from the focus point by the recorded deviation from the focuspoint.
 13. An optical disc recording/reproducing apparatus, comprisingan optical pickup for emitting light on a track of an optical disc onwhich address information is recorded beforehand, and outputting asignal according to light reflected from the optical disc, and a signalgenerating unit for generating a reproduction signal and a focus errorsignal on a basis of an output of the optical pickup, the focus errorsignal corresponding to a deviation of a focus of emitted light from afocus point, the optical disc recording/reproducing apparatus aligningthe focus of light with the focus point according to the focus errorsignal to record and reproduce data, wherein the apparatus furthercomprises: a unit for displacing the focus of light from the focus pointby supplying a deviation value to the focus error signal, a unit forrecording data while displacing the focus of light from the focus point,and detecting a reading state of address information from thereproduction signal having been generated by reproduction on a recordingarea, a unit for recording data while displacing the focus of light fromthe focus point, and detecting an amplitude value of the reproductionsignal having been generated by reproduction on the recording area, anda unit for determining a deviation from the focus point with a bestreading state of address information and a deviation from the focuspoint with a maximum amplitude value of the reproduction signal, thedeviations being determined on a basis of a relationship among thedetected reading state of data, the detected amplitude value of thereproduction signal, and a deviation from the focus point when data isrecorded while the focus of light is displaced from the focus point, theunit determining and recording an optimum deviation for recording fromthe focus point on a basis of the deviations, wherein data is recordedwhile the focus of light is displaced from the focus point by therecorded deviation from the focus point.
 14. An optical discrecording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, and a signal generating unit forgenerating a reproduction signal and a focus error signal on a basis ofan output of the optical pickup, the focus error signal corresponding toa deviation of a focus of emitted light from a focus point, the opticaldisc recording/reproducing apparatus aligning the focus of light withthe focus point according to the focus error signal to record andreproduce data, wherein the apparatus further comprises: a unit fordisplacing the focus of light from the focus point by supplying adeviation value to the focus error signal, a unit for detecting areading state of address information from the reproduction signal havingbeen generated by light reflected from the optical disc when data isrecorded while the focus of light is displaced from the focus point, anda unit for determining and recording a deviation from the focus pointwith a best reading state of address information, the deviation beingdetermined on a basis of a relationship between the detected readingstate of address information and the deviation from the focus point whendata is recorded while the focus of light is displaced from the focuspoint, wherein data is recorded while the focus of light is displacedfrom the focus point by the recorded deviation from the focus point. 15.An optical disc recording/reproducing apparatus, comprising an opticalpickup for emitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, a signal generating unit forgenerating a reproduction signal on a basis of an output of the opticalpickup, and a unit for inclining an optical axis of light emitted to theoptical disc and adjusting an inclination angle of the optical axis oflight with respect to a surface of the optical disc, the optical discrecording/reproducing apparatus adjusting the inclination angle of theoptical axis of light with respect to the surface of the optical disc torecord and reproduce data, wherein the apparatus further comprises: aunit for displacing the inclination angle of the optical axis of lightwith respect to the surface of the optical disc, a unit for recordingdata while displacing the inclination angle of the optical axis of lightwith respect to the surface of the optical disc, and detecting a readingstate of address information from the reproduction signal having beengenerated by reproduction on a recording area, and a unit fordetermining and recording an inclination angle for obtaining a bestreading state of address information, the inclination angle beingdetermined on a basis of a relationship between the detected readingstate of address information and the inclination angle when data isrecorded while the inclination angle of the optical axis of light isdisplaced with respect to the surface of the optical disc, wherein datais recorded while the optical axis of light is inclined by the recordedinclination angle.
 16. An optical disc recording/reproducing apparatus,comprising an optical pickup for emitting light on a track of an opticaldisc on which address information is recorded beforehand, and outputtinga signal according to light reflected from the optical disc, a signalgenerating unit for generating a reproduction signal on a basis of anoutput of the optical pickup, and a unit for inclining an optical axisof light emitted to the optical disc and adjusting an inclination angleof the optical axis of light with respect to a surface of the opticaldisc, the optical disc recording/reproducing apparatus adjusting theinclination angle of the optical axis of light with respect to thesurface of the optical disc to record and reproduce data, wherein theapparatus further comprises: a unit for displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, a unit for recording data while displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, and detecting a reading state of data from the reproduction signalhaving been generated by reproduction on a recording area, and a unitfor determining and recording an inclination angle for obtaining a bestreading state of data, the inclination angle being determined on a basisof a relationship between the detected reading state of data and theinclination angle when data is recorded while the inclination angle ofthe optical axis of light is displaced with respect to the surface ofthe optical disc, wherein data is recorded while the optical axis oflight is inclined by the recorded inclination angle.
 17. An optical discrecording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, a signal generating unit forgenerating a reproduction signal on a basis of an output of the opticalpickup, and a unit for inclining an optical axis of light emitted to theoptical disc and adjusting an inclination angle of the optical axis oflight with respect to a surface of the optical disc, the optical discrecording/reproducing apparatus adjusting the inclination angle of theoptical axis of light with respect to the surface of the optical disc torecord and reproduce data, wherein the apparatus further comprises: aunit for displacing the inclination angle of the optical axis of lightwith respect to the surface of the optical disc, a unit for recordingdata while displacing the inclination angle of the optical axis of lightwith respect to the surface of the optical disc, and detecting anamplitude value of the reproduction signal having been generated byreproduction on a recording area, and a unit for determining andrecording an inclination angle for obtaining a maximum amplitude valueof the reproduction signal, the inclination angle being determined on abasis of a relationship between the detected amplitude value of thereproduction signal and the inclination angle when data is recordedwhile the inclination angle of the optical axis of light is displacedwith respect to the surface of the optical disc, wherein data isrecorded while the optical axis of light is inclined by the recordedinclination angle.
 18. An optical disc recording/reproducing apparatus,comprising an optical pickup for emitting light on a track of an opticaldisc on which address information is recorded beforehand, and outputtinga signal according to light reflected from the optical disc, a signalgenerating unit for generating a reproduction signal on a basis of anoutput of the optical pickup, and a unit for inclining an optical axisof light emitted to the optical disc and adjusting an inclination angleof the optical axis of light with respect to a surface of the opticaldisc, the optical disc recording/reproducing apparatus adjusting theinclination angle of the optical axis of light with respect to thesurface of the optical disc to record and reproduce data, wherein theapparatus further comprises: a unit for displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, a unit for recording data while displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, and detecting a reading state of address information from thereproduction signal having been generated by reproduction on a recordingarea, a unit for recording data while displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, and detecting a reading state of data from the reproduction signalhaving been generated by reproduction on the recording area, and a unitfor determining an inclination angle for obtaining a best reading stateof address information and an inclination angle for obtaining a bestreading state of data, the inclination angles being determined on abasis of a relationship among the detected reading state of addressinformation, the detected reading state of data, and the inclinationangle when data is recorded while the inclination angle of the opticalaxis of light is displaced with respect to the surface of the opticaldisc, the unit determining and recording an optimum inclination anglefor recording on a basis of the inclination angles, wherein data isrecorded while the optical axis of light is inclined by the recordedinclination angle.
 19. An optical disc recording/reproducing apparatus,comprising an optical pickup for emitting light on a track of an opticaldisc on which address information is recorded beforehand, and outputtinga signal according to light reflected from the optical disc, a signalgenerating unit for generating a reproduction signal on a basis of anoutput of the optical pickup, and a unit for inclining an optical axisof light emitted to the optical disc and adjusting an inclination angleof the optical axis of light with respect to a surface of the opticaldisc, the optical disc recording/reproducing apparatus adjusting theinclination angle of the optical axis of light with respect to thesurface of the optical disc to record and reproduce data, wherein theapparatus further comprises: a unit for displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, a unit for recording data while displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, and detecting a reading state of data from the reproduction signalhaving been generated by reproduction on a recording area, a unit forrecording data while displacing the inclination angle of the opticalaxis of light with respect to the surface of the optical disc, anddetecting an amplitude value of the reproduction signal having beengenerated by reproduction on the recording area, and a unit fordetermining an inclination angle for obtaining a best reading state ofdata and an inclination angle for obtaining a maximum amplitude value ofthe reproduction signal, the inclination angles being determined on abasis of a relationship among the detected reading state of data, thedetected amplitude value of the reproduction signal, and the inclinationangle when data is recorded while the inclination angle of the opticalaxis of light is displaced with respect to the surface of the opticaldisc, the unit determining and recording an optimum inclination anglefor recording on a basis of the inclination angles, wherein data isrecorded while the optical axis of light is inclined by the recordedinclination angle.
 20. An optical disc recording/reproducing apparatus,comprising an optical pickup for emitting light on a track of an opticaldisc on which address information is recorded beforehand, and outputtinga signal according to light reflected from the optical disc, a signalgenerating unit for generating a reproduction signal on a basis of anoutput of the optical pickup, and a unit for inclining an optical axisof light emitted to the optical disc and adjusting an inclination angleof the optical axis of light with respect to a surface of the opticaldisc, the optical disc recording/reproducing apparatus adjusting theinclination angle of the optical axis of light with respect to thesurface of the optical disc to record and reproduce data, wherein theapparatus further comprises: a unit for displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, a unit for recording data while displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, and detecting a reading state of address information from thereproduction signal having been generated by reproduction on a recordingarea, a unit for recording data while displacing the inclination angleof the optical axis of light with respect to the surface of the opticaldisc, and detecting an amplitude value of the reproduction signal havingbeen generated by reproduction on the recording area, and a unit fordetermining an inclination angle for obtaining a best reading state ofaddress information and an inclination angle for obtaining a maximumamplitude value of the reproduction signal, the inclination angles beingdetermined on a basis of a relationship among the detected reading stateof address information, the detected amplitude value of the reproductionsignal, and the inclination angle when data is recorded while theinclination angle of the optical axis of light is displaced with respectto the surface of the optical disc, the unit determining and recordingan optimum inclination angle for recording on a basis of the inclinationangles, wherein data is recorded while the optical axis of light isinclined by the recorded inclination angle.
 21. An optical discrecording/reproducing apparatus, comprising an optical pickup foremitting light on a track of an optical disc on which addressinformation is recorded beforehand, and outputting a signal according tolight reflected from the optical disc, a signal generating unit forgenerating a reproduction signal on a basis of an output of the opticalpickup, and a unit for inclining an optical axis of light emitted to theoptical disc and adjusting an inclination angle of the optical axis oflight with respect to a surface of the optical disc, the optical discrecording/reproducing apparatus adjusting the inclination angle of theoptical axis of light with respect to the surface of the optical disc torecord and reproduce data, wherein the apparatus further comprises: aunit for displacing the inclination angle of the optical axis of lightwith respect to the surface of the optical disc, a unit for detecting areading state of address information from the reproduction signal havingbeen generated by light reflected from the optical disc when data isrecorded while the inclination angle of the optical axis of light isdisplaced with respect to the surface of the optical disc, and a unitfor determining and recording an inclination angle for obtaining a bestreading state of address information, the inclination angle beingdetermined on a basis of a relationship between the detected readingstate of address information and the inclination angle when data isrecorded while the inclination angle of the optical axis of light isdisplaced with respect to the surface of the optical disc, wherein datais recorded while the optical axis of light is inclined by the recordedinclination angle.